1. Field of the Invention
The present invention relates to an image processing apparatus (an image forming apparatus), and particularly relates to the image processing apparatus that is characterized in a human body (living body) detection technique for switching an electric power mode.
2. Description of the Related Art
A conventional image processing apparatus supports a power saving mode in which electric power supplied to almost all units inside the apparatus is cut in order to achieve power saving. Since a return to a normal mode from the power saving mode needs to turn on a power, time is taken, which may impair a user's convenience.
In order to solve the problem, some conventional image processing apparatuses that support the power saving mode are provided with a human body detection unit and return to the normal mode from the power saving mode when detecting a human body (for example, see Japanese laid-open patent publication (Kokai) No. H11-202690 (JP H11-202690A)). This has an effect to shorten an apparent starting time for a user.
In the technique disclosed in the above-mentioned publication, since the image processing apparatus returns to the normal mode whenever the user approaches the image processing apparatus, the apparatus uselessly returns to the normal mode even when it is unnecessary.
For example, it is necessary to return to the normal mode when the user operates an operation unit. However, it is unnecessary to return the image processing apparatus from the power saving mode when coming to pick up ejected paper to a paper ejection unit, when supplementing paper to a paper feeding unit, and when supplying toner. Unnecessary start-up of the image processing apparatus uselessly consumes lives of devices of which the numbers of times of start-up are limited.
For example, the devices of which lives are limited include a HDD, a relay that turns on/off electric power in an electric power source unit, a fuse used in the electric power source unit, etc. Moreover, unnecessary electric power is consumed until the once-started image processing apparatus shifts to the power saving mode again.